You can get this exception from Unity: Activation error occured while trying to get instance of type in many cases. And then you can try to look into InnerException stack to find only The type MyType cannot be constructed. You must configure the container to supply this value.. Below are the reasons that can lead to this error message:

The class you try instantiate (or dependent class) is abstract.

The class you try instantiate (or dependent class) has no public constructor.

OpenId is a way of authenticating yourself on the increasing number of websites that support it. OpenId itself looks like url address, something similar to "janedoe.openid.com". There are several OpenId providers you can get your OpenId address from, but wouldn't it be nice to have "yoursite.com" for OpenId instead of "somename.someopenidprovider.com"? Apart from looking cool, it's a good way to promote your site as your OpenId is often displayed in signature field even where other html links are disallowed.

When you search for "drupal syntax highlighting" you will likely get a lot of results involving installation of modules most of them still in beta stage of development. Most of the code you'll find is using SyntaxHighlighter library, which is easy to install and use. Indeed, this excellent library is so easy to use, you don't need any module at all to take advantage of it on your Drupal site. Here's step-by-step tutorial: